The gunship shook like a heart in a fist. Restraint bars rattled against ceramite as the Night's Children dropped out of Luna's shadow and plunged toward the small red coin of Deimos. Inside the bay, fifty suits of Mark III sat shoulder to shoulder in two facing ranks, no heraldry, no laurels—bare cobalt plates and serial cut into the breast. Helm lenses showed only the reflections of other lenses. When they breathed, it was in a measured chorus, two hearts finding one cadence.
Kael sat at the head of First Squad, helm locked, boltgun laid across his thighs. He watched status glyphs tick from amber to green along his display as the cabin pressure bled down. The smell was machine oil, propellant residue, old steel; the taste of air through the rebreather was metallic and dry. He had been hungry all his life; now he ate air and violence and called it discipline. Outwardly he was everything they had made: quiet, exact, without edges to snag on sentiment. Inwardly, thought moved like a knife through cloth, testing the seams—why men broke, where fear lived in the body, which choice ended the fight fastest and left the fewest names to remember.
The vox clicked; Commander Var Juren's voice came thin through the hull, transmitted from the command picket above Deimos. "Objective is Penal Delta-Seven. Forty thousand souls registered before the mutiny. Overseers killed, defense grid captured, orbital batteries cold. We take it back intact. No atomic option. No wide-spectrum bombardment. This is instruction. The Emperor observes."
No affirmation. None expected. The gunship's forward blast shields retracted half a span; Deimos rolled into view—a rock scabbed in iron, its prison a ring of linked habitats braced by struts, its skin stippled with gun-towers and corrosion. Beyond it, Mars burned dull red, patient as an old god.
"Thirty seconds," the crew chief barked. His voice sounded small in the steel. "Squads one and two, west ingress. Three and four, south ingress. Stay off the main thoroughfares until we cut their grid."
Kael rose with the rest as the harness locks blew. The deck vibrated harder as retro-thrusters fought momentum; gravity leaned and then gave up. He felt the armour through the Black Carapace as intimately as skin; micro-servos hummed like content predators along his spine. He signalled without words—two fingers down, one sweep right—and First Squad stood into the descent frame with a precision that soothed something in him that Terra had never soothed.
Impact hit like a verdict. The gunship's mag-clamps kissed the landing struts to the tower spine and bit; the ramp fell on a burst of hydraulic breath. Heat rolled in with the light—the sour, hot stink of bad recirculation, unwashed bodies, and hot metal. Bullets snapped off the ramp's lip, whining, flattened to bright petals on the threshold. Someone screamed in the open spaces beyond, a high civilian sound that didn't belong in the music of a war. Kael's optics painted a corridor of ferrocrete and ribbed hab-pipe, emergency lumens bleeding red along the ceiling. The first defenders appeared at the far bulkhead, prison gray and stolen armour plates taped together like guilt, weapons clutched in white-knuckled hands.
"Advance," Kael said, calm as water poured from a height. First Squad flowed from the ramp, bolters low. The first prisoner lifted a stubber. Malchion's shot took him under the sternum and ripped the man open in a mist that hung in the hot air like breath in winter. Another defender leaned from a service arch to fire wide; Joras's burst cored the side of his neck, and the man pinwheeled into a rail, arterial spray painting bright commas on the wall before his body slumped. The corridor smelled immediately of copper and propellant, a wet, hungry smell that the armour's filters could thin but not erase.
They moved in a methodical rush, boots sucking at pooled fluids, shells clinking as they drummed the deck underfoot. Kael's internal clock kept the pace: five-count bursts, three-count advance, muzzle discipline enforced by habit older than any of them: do not waste, do not panic. He felt his mind do what it had been trained to do—measure. The angle of a shoulder telegraphed the line of a shot; the tremor in a hand foretold the failure of nerve. He let the information pass through him and settle, with the indifferent grace of a butcher laying cuts on the right hooks.
They reached the first interchange: a spider web of catwalks over a dropshaft that fell four decks and ended in darkness. Voices throbbed up from below—chanting, uneven, the sound of men trying to make themselves bigger with noise. Kael looked once and saw the geometry: fifty hostiles at the base, improvised barricade of tram cars and pallets, line of fire up through the shaft. He closed his left fist twice. Joras handed off to the second marksman and stepped to the rail, low and invisible, breath a metronome.
Six shots: the tops of skulls blooming like crushed fruit as silhouettes rose to fire through the grill. The chanting collapsed into ragged shouts. Malchion heaved a tram car's carcass over and it went down the shaft in a clangor of tearing metal, smashing the barricade and three men beneath, the impact cracking bones loud enough to be felt through the rails. Screams braided into a single animal sound. Kael tasted bile and ash and thought: this is instruction, too.
"Down the service rung," he ordered. "No ropes. Stagger the drop."
They went in pairs. Hands found rung, boots bit steel, armour scraped. Blood smeared onto gauntlets where other men had held in terror and slipped. Kael dropped last. He landed in the broken ruin of the barricade amid a litter of glass and splinters and soft things that had been inside other things seconds before. A prisoner lunged with a crowbar; Kael took the blow on his pauldron, felt it ring through the ceramic, and cut the man across the clavicles. The chain-teeth bit; the body jerked; blood pattered on his boots in warm, irregular taps.
Bulk doors led off the shaft base. Prisoners surged in the left one—a clot of desperate men pressed by those behind, faces gray with fear and dust. Kael threw a hand up. "Hold fire."
The Night's Children froze, the discipline shocking in its immediacy. Kael stepped forward. His armour creaked. The crush stalled; eyes widened; the front rank stopped because the back pressed and the back pressed because the front stopped. He raised his boltgun, sighted low, and fired twice. Kneecaps exploded. The men fell, screaming, a sudden gap opening in the press; those behind saw the gap and their courage left them like breath. He did not fire again. He watched them break. He heard their terror become decision.
"Hands on heads," he said. "Kneel. Now."
They knelt. A few tried to run. A single shot for each runner, back of skull, clean. The others stayed, learning the lesson their bodies already knew: you cannot run faster than inevitability.
"Cuff them," Kael told the reserve fireteam. "Stack them along the rail. If anyone moves, shoot the man to his left." Acknowledgments clicked. The squad set to it, efficient, brutal without relish. Malchion drew breath, let it out in a hiss.
"There's a smell here." He meant more than the blood; he meant the rot of a place where fear had been a sport.
"Remember it," Kael said. He didn't look at him. He was looking down a corridor that ended in the hard glow of a power room. His auspex showed heat signatures clustered around the primary breaker array, thirty bodies, weapons drawn, the cameras dark. The prison had stolen sight as well as speech.
"Grid is there," Silas voxed from the rear element, voice wrapped in electrum calm. "They've cut half their own feeds. I can bring it back if I get my hands on the panel."
"You'll have them," Kael said.
"First Squad, on me. Second, cover the shaft. Third, take the right corridor and clear to the hydro pumps—no ruptures. Fourth, hold these prisoners and keep them scared enough to obey."
He took the left-hand passage at a steady walk, muzzle down, situational map unrolling in his mind. The corridor narrowed—a choke. He halted them a body-length back from the corner. A voice shouted ahead, breaking into a higher register; boots scraped; someone sobbed. He could feel fear in the air like humidity.
"Joras," he said. The marksman slid past, placed his muzzle against the wall at head height, angle calculated, and fired once. A man screamed on the other side, high and brief. A body fell and hit the panel with a heavy, wet sound. Kael rounded the corner and went in, low.
The power room was a rectangle of humming cabinets and cable trunks. The prisoners had built a makeshift redoubt with overturned lockers. The floor in front of it was slick; the leather soles of scavenged boots had skated; his sabatons did not. A man popped up, fired a pump shotgun, the pellets slapping Kael's pauldron and helm like thrown gravel; Kael shot him through the mouth.
Teeth and bone spattered the locker behind; the body sagged before the brain finished understanding. Malchion took the next two with surgical bursts that put shoulders out of the game. Someone rushed with a mining pick; Joras shot his foot and the man screamed, toppled, tried to crawl; Kael put a boot on his spine and pressed until something gave like stale bread, then stepped over him as one step in a march.
The last five broke and ran for the far door. Kael raised his weapon, then didn't. "Let them," he said. "They'll carry the right story."
The right story was this: the Night's Children come and the world tightens around your throat until you remember how to breathe properly. Silas shouldered past a cooling cabinet, hands already on the breaker panel. "Power to main," he murmured. "Camera grid rebooting. I have their eyes."
"Then they're done," Kael said. He felt nothing like triumph, just the clean click of a mechanism returning to true. He switched to the battlenet. "Commander—primary grid secured. West ingress stable. We have prisoners stacked and breathing. Proceeding to central control."
Var Juren's reply was immediate, edged with approval he didn't waste. "Continue, Section Leader. Minimal damage recorded. The Emperor will be satisfied."
He cut the line and moved again, thoughts keeping pace—counting ammunition expenditure, checking heart rates, watching for the tremor in Malchion's left hand that meant fatigue, the tiny signs that separated a clean operation from a messy one. In an unused corner of his mind, he wondered how many of these men could have lived differently if someone had taught them the lesson earlier, if the first fear had been a warning, not a hobby. He left the thought where it belonged: nowhere useful. The work remained.
They took central control twenty minutes later without losing a single brother. The prison governor—a man with soft hands and a broken nose—lay in a corner, face swollen purple where his own people had beaten him before the mutiny ate them too. Kael hauled him up by the collar, shoved him into the vox chair, wiped blood off the microphone with a thumb.
"Speak," he said.
The man's eyes darted, caught on Kael's black lenses, and stilled. "What—what do I say?"
"The truth," Kael said. "You surrendered. You are grateful. You are alive because we chose that order."
The governor began to talk. His voice shook. It didn't matter; fear was a signal amplifier. Across Deimos, doors began to open. Men threw down weapons. A few tried to fight and died. Most remembered.
Kael listened to the systems come back like a living thing learning to breathe again—pumps thumping, fans whining as grit scraped free, lumens filling hallways with an ugly, merciful light. He watched prisoners kneel in shimmering feeds, hands on heads, eyes wide and wet. He watched his brothers move among them—huge, patient, the weight of inevitability passing down ranks that had known too much contingency.
Blood dried on his boots in stiff flakes. A smear across his gauntlet had gone from bright to brown to black. He noticed the progression the way a machinist notices a bearing's wear pattern—catalogued; compared; filed for later.
"Section Leader," Malchion said over a low channel. "You saved two of them at the barricade."
"I saved ammunition," Kael said.
"Is that what we're calling mercy?"
"It's what mercy looks like when it works," Kael answered, and let it be both true and deflection.
Above them, Var Juren's final order came through: "Deimos secured. Good work. Lock it down and stand by to return to Luna. The Emperor has seen enough."
Kael looked at the vox chair, at the governor's shaking hands, at the feeds full of men suddenly very small. He thought of Terra's Sink and the knife, the lesson nobody had taught until he taught it to himself. He thought of fear as a language and wondered, for one quiet, private breath, whether he would ever stop speaking it.
"First Squad," he said aloud, voice steady again. "Form on me. We finish the count. Then we leave it quieter than we found it."
They moved. The floor squeaked under drying blood. A droplet hung from the muzzle of Kael's boltgun and fell, slow as a decision. He didn't watch it hit. He was already walking into the next corridor, where the air smelled like hot metal and terror and the future.
When the last cell was opened and the last gun laid down, the Night's Children began the quiet work of correction.
They moved through the prison's arteries like black blood. The hum of machinery replaced the earlier chorus of screams. The only sounds now were the measured tread of ceramite boots and the hiss of recirculated air struggling to clear the iron smell that clung to everything.
Kael stood in what had been the overseer's hall—a glass-walled promenade above the main yard. From here the penal colony looked like a dissected insect: decks cut open, cargo frames dangling, lights bleeding red where the power grid still limped back to life. Below, the prisoners knelt in long ranks, heads shaved, hands locked behind skulls, overseers posted at ten-pace intervals. Every twenty meters a corpse lay where someone had misunderstood an order.
Commander Var Juren's landing craft hung above the yard like a blade. When it settled, the wash of its engines blew blood and dust across the ranks, staining the gray uniforms darker. Var Juren disembarked flanked by two aides in crimson enviro suits. He didn't shout. He simply walked to the railing where Kael waited.
"Section Leader Varan," he said. "Report."
Kael removed his helm. The movement drew no gasp; they all looked like him now—skin pale as stone, eyes black from edge to edge. "Primary grid secured. All sectors compliant. Civilian casualties estimated at twenty-seven thousand. Enemy casualties, one hundred percent."
Var Juren's biological eye blinked once; the augmetic stayed steady. "Your tone is efficient. I approve of efficiency. But remember the difference between efficiency and indifference."
Kael looked down at the lines of prisoners. "We could have purged them all. They'll rebuild the colony instead."
"Because you allowed them to."
"Because the Emperor ordered us to keep it intact."
Var Juren studied him for a moment that lasted long enough to be uncomfortable. "You're learning the script, Varan. The Emperor values instruments that think, but He discards the ones that question."
Kael almost smiled. "Then I'll keep my questions quiet."
"Do that. Gather your squads. We'll make a show for the remembrancers before we return to Luna."
The display was simple. The yard was cleared, the bodies removed, the prisoners arranged into geometric order: ten thousand on each of four quadrants, heads bowed. The Night's Children stood above them, silent. When Var Juren spoke through the loudhailers, his voice filled the entire dome.
"Deimos remembers fear again. Deimos remembers obedience. That is the Emperor's mercy."
Kael watched the prisoners, watched how their shoulders tightened at the words fear and obedience. He recognized it—understanding, not devotion. Fear could teach. He believed that more than he believed in mercy.
Later, aboard the command ship Auric Silence, the legionaries filed through the decontamination sluices, steam curling off their armour in ghost shapes. The medicae teams moved like priests, sponging blood from plates, noting fractures, replacing dented pauldrons. Kael sat on the inspection bench while a servitor scrubbed a line of dried gore from the seams of his breastplate. The sound was soft, intimate, the rasp of brush on metal.
Malchion sat beside him, helm off, face streaked where sweat had run through the ash. "You ever wonder if we scare ourselves?"
Kael looked at him. "Do you?"
"Sometimes. When it's quiet after. Feels like the ghosts are counting us."
Kael considered. "Then don't let them finish."
Malchion laughed, short and low. "Always an answer."
"Always an instruction."
Across the bay, Joras and Silas were re-arming the squads, methodical as clockwork. The smell of solvent hung thick; the sound of distant machinery beat in time with Kael's second heart. He felt the calm that came after battle—a clarity edged with exhaustion. His mind replayed the images: the prisoner's eyes when he knelt, the colour of the blood under red light, the weight of the silence when the shooting stopped. He told himself that cataloguing them was duty, not guilt. Duty was easier.
When Var Juren gathered the Company for dismissal, he spoke without ceremony. "You have performed as the Emperor expected. Deimos will remain productive. The Mechanicum has already claimed its forges. We return to Luna for refit. You will rest, study, and remember. The next operation will be greater in scale."
He paused. "Section Leader Varan—step forward."
Kael obeyed. The Commander's augmetic eye clicked softly as it focused. "You showed initiative and restraint. You will be promoted to Acting Captain of the Fifteenth Company pending confirmation from the Sigillite's office. Do not let pride rot it. You will be measured by your results, not your rank."
Kael nodded once. "Understood."
"Good. Dismissed."
The flight back to Luna was quiet. Through the porthole, Kael watched Deimos shrink to a black stone circled by new lines of construction—slave columns already rebuilding under Mechanicum supervision. The galaxy beyond was a tapestry of dust and slow fire. He thought of what Juren had said about questions. He had many now: why fear worked better than faith, why obedience required blood to mean anything, why his eyes, all their eyes, were black.
He rested his head against the hull. For a moment, he saw his reflection there, faint and ghost-thin, and thought that maybe they had built something that would outlast even the Emperor's idea of mercy.
When Luna's pale horizon rose to meet them, Kael closed his eyes and let the machine carry him home. He dreamed—not of war, but of quiet corridors where no one was afraid.
He woke knowing he would never see such corridors in life.